Abstract:[Objective] The characteristics and internal relations for multiple time scale runoff in urbanized Qinhuai River basin were explored in order to provide scientific basis for quantitatively evaluating the impact of climate change and anthropogenic activities on the process of water cycle. [Methods] Based on the long-term hydro-meteorological and impervious surface data during 1986—2015 in Qinhuai River basin, the Mann-Kendall trend test and Pettitt change-point test were combined to identify the trends and abrupt change points of the precipitation and runoff series. The influence of rainfall and impevious coverage on runoff changes at different time scales was analyzed by using established generalized additive models for location, scale and shape (GAMLSS) framework. [Results] ① The impervious surface had expanded rapidly in 30 years, with the impervious rate increased from 3.09% in 1988 to 24.01% in 2015. ② The characteristics of runoff series at different time scales were various, and the annual runoff series showed a significantly upward trend with an obvious abrupt change point at 2001. ③ The impervious surface expansion had a more significant impact on small intensity flood, for the same time scale, normally, the impervious surface had a greater impact on small runoff series than on high runoff series. Further, the imperviousness has cumulative effect with the increase of time scale. [Conclusion] The urbanization process of Qinhuai River basin is accelerating, and the effects of impervious surface expansion on multiple time scale runoff are various.